It's "nonsensical" to split the role of chairman and CEO at JPMorgan Chase when Jamie Dimon has such a strong track record leading the bank, former board member Lawrence Bossidy told CNBC on Thursday.
At next week's JPMorgan annual meeting, the two biggest U.S. proxy advisors, Institutional Investor Services and Glass Lewis, are pushing a nonbinding proposal to separate the chairman and CEO roles held by Dimon.
(Read More: JPMorgan Chief's Fate Comes Down to Close Vote)
"The guy has done everything asked of him," Bossidy continued. "I can't help to think it's misdirected and misguided."
ISS and Glass Lewis have said that last year's more than $6 billion worth of "London Whale" trading losses raises questions about oversight.
"Even though they have the 'London Whale'," Bossidy said, Dimon "acknowledged his accountability for it and he took decisive action to overcome it."
"Since Dimon has been [at JPMorgan], he navigated through the 2008 financial collapse without any problem," Bossidy said. "Thereafter, they've had three record years of earnings."
Meanwhile, Tim Bush of the British pension fund advisor Pension & Investment Research Consultants said he supports the split but for different reasons. He told CNBC it's a matter of principle because it's unlikely that someone of Dimon's caliber would always be in those positions.
(Read More: Jamie Dimon—It's Not all About You: Pension Advisor)
Bossidy, who served on the JPMorgan board from 1998 to 2006, said he supports the concept of a lead director, which can hold corporate leaders accountable instead of making the chairmanship of a company separate from the CEO.